SpotTheTroll.org, from the Clemson University Media Forensics Hub, is an interactive quiz that asks readers to examine real social media content and determine whether they are from a legitimate account or an internet troll.
In Science magazine, David M. J. Lazer, et. al. define fake news as follows:
"[F]abricated information that mimics news media content in form but not in organizational process or intent. Fake-news outlets, in turn, lack the news media’s editorial norms and processes for ensuring the accuracy and credibility of information. Fake news overlaps with other information disorders, such as misinformation (false or misleading information) and disinformation (false information that is purposely spread to deceive people)."
(Source)
"How to Spot Fake News," FactCheck.org
FactCheck.org's eight-step guide to spotting fake news stories on the internet.